1. Technical Field
The present invention relates in general to motor vehicle pedals. More particularly, but without restriction to the particular embodiment and/or use which is shown and described for purposes of illustration, the present invention relates to pedal systems that provide for adjustment of the brake, clutch, or accelerator pedal relative to a vehicle driver.
2. Discussion
In a conventional automobile, pedals are provided for controlling the acceleration and braking functions of the vehicle. If the vehicle includes a manual transmission, a clutch pedal is typically provided. In most motor vehicles today, the pedals have fixed locations. Typically, these pedals are fixed to the body of the vehicle at a point, so that the pedal will pivot about the fixed point when foot pressure is applied by the operator. In order to accommodate driver""s of varying physiques, the driver""s seat is, generally, slidingly engaged to the vehicle such that a driver can position himself or herself relative to either the steering wheel or the pedals. This adjustment provides, to a certain degree, an improvement of driver comfort.
However, it is nearly impossible to such a single adjustment to accommodate all possible variances in human physiques. In particular, the proportional relation between the lengths of a driver""s arms and legs in relation to the drivers overall torso size cannot be accommodated through a single adjustment. For example, many smaller people have small legs. Therefore, when they drive a motor vehicle, they must position the seat in its foremost position to properly reach the pedals. Unfortunately, their arms and torso are typically too close to the steering wheel of the vehicle to be comfortable. Accordingly, it has been widely recognized that some type of pedal adjustment is desirable to provide optimal comfort to the driver while he or she is operating the vehicle.
Many approaches to providing adjustable pedals have been suggested in the prior art. The most common approach is to provide some type of pushrod, ratcheting, or camming device so that the pedal will operate in a different pivotal range. By utilizing such a device, the static position of the pedal can be modified in the forward and rearward direction. An example of this approach is provided in U.S. Pat. No. 5,771,752, issued Jun. 30, 1998. Although, in general, this type of system works satisfactorily in providing an adjustable pedal, the distance of the pedal to the floor will change as the pedal is pivoted. This may be not desirable because it changes the angle at which foot pressure needs to be applied, and may affect the angle at which the master cylinder pushrod for a brake pedal is activated.
Many other adjustable pedal systems have been developed in the recent years that provide a linear movement of the pedals so as to maintain the relationship between the pedal and floor. A few examples of such applications can be found in U.S. Pat. No. 4,870,871, issued Oct. 3, 1989, U.S. Pat. No. 5,722,302, issued Mar. 3, 1998, and U.S. Pat. No. 5,010,782, issued Apr. 30, 1991. Although prior art devices such as those described above have proven to be successful, there is a need to develop a system that can be implemented on a vehicle currently in production while, effective, robust, and compact enough to be used in future vehicle development efforts. The present invention also represents substantial improvements over the pedal design disclosed in the aforementioned patents.
Accordingly, it is a principal objective of the present invention to provide a truly versatile and effective adjustable pedal apparatus for use in a motor vehicle.
It is another objective of the present invention to provide an adjustable pedal apparatus that can mimic the action of a standard pedal to the master cylinder pushrod while being linearly adjustable in the longitudinal direction.
It is still another objective of the present invention to provide an adjustable pedal apparatus that includes structure to lock the pivot pin of the pedal in position only while the pedal is depressed.
It is a further objective of the present invention to provide an adjustable pedal apparatus that can be utilized in an existing vehicle with minimal modification, while effective, robust, and compact enough to be utilized in future vehicle development efforts.
In one form, the present invention provides an adjustable pedal apparatus for a motor vehicle. The apparatus includes a pedal having a pivot pin disposed near the top end thereof and a footpad disposed near the bottom end thereof. The pedal can be translated in a longitudinal manner parallel to the floor of the motor vehicle. The apparatus also includes a body structure that is attached to the body or chassis of the motor vehicle. The body structure includes a first and second longitudinally extending slots, the first being elevated from the second. The elevated first slot is adapted to receive the pivot pin and to allow for movement of said pivot pin within said first slot. The body structure also has a motion linkage pivotally connected thereto. The pivoting of the motion linkage is designed to mimic the swing of a non-adjustable brake pedal. A tie rod is pivotally attached to the motion linkage and pivotally attached to an attaching unit that is disposed about a screw. The screw extends from the attaching unit and is pivotally and threadedly attached to the pedal via a threaded unit. The attaching unit is received by the second longitudinally extending slot in the body structure. Attaching unit is fixed in position by flanges disposed on the screw. Attaching unit includes a bore of a diameter greater than that of the screw, such that the screw is allowed to rotate freely therein. The pushrod controlling the desired vehicle function is attached to either the tie rod or the motion linkage. This will provide uniform motion for the pushrod when the pedal is depressed irrespective of the longitudinal location of the pedal. A motor is attached to the screw to cause movement of the pedal about the screw. As the screw is translated rearward the attaching unit contacts an abutment formed by the second slot and forces the threaded pedal attachment to translate the pedal rearward. Accordingly, the pivot pin in the first slot translates rearward therewith. As the screw is translated forward the pushrod keeps the attaching unit substantially in place while the pedal, including the pivot pin in the first slot, is translated forward. When the pedal is in the static or non-depressed position the pivot pin is free to translate within the first slot. As soon as the pedal is depressed the pivot pin is locked in place. This is accomplished by a cam, locking mechanism, and spring arrangement. A series of teeth are disposed on the body structure above the first slot, and a lever having mating teeth is pivotally attached to the pedal. The lever is biased towards the pedal by interconnecting the pivot pin and the lever by a spring element. The spring element ensures contact between the teeth on the body structure and the mating teeth on the lever while the pedal is depressed. When the pedal is not depressed, i.e. the static position, a cam formation on the top portion of the pedal contacts the lever. The cam formation acts against the biasing force of the spring to disengage the two sets of teeth, thereby allowing the pivot pint to translate freely within the first slot. It can be appreciated that longitudinal movement of the pedal is designed to occur only when the pedal is in the static position.
Additional benefits and advantages of the present invention will become apparent to those skilled in the art to which this invention relates from a reading of the subsequent description of the preferred embodiment and the appended claims, taken in conjunction with the accompanying drawings.